The GenomicdBioinformatics core was established to assist PPG member laboratories in the application of genomic technologies from experimental design and data acquisition to the analysis of complex data sets. The genomic component of the core, under the guidance of Dr. Lynda Chin, will provide microarray infrastructure and mouse and human cDNA repositories for expression profiling as well as provide the necessary scientific and technical expertise in the design, execution and interpretation of the expression profiling and array-CGH experiments. The bioinformatics component will provide the critical computing support needed for the storage, manipulation and analysis of information obtained from both expression profiling and aCGH profiling experiments by all three prqjects of the PPG. Dr. Wing Wong, a leader in bioinformatics, will guide the PPG in this area. Justification for this core derives from the facts that it provides quality control and standardization for cross utilization of data among the diverse systems and species used in the various projects and that makes available to all PPG members highly specialized equipment, unique reagents and centralized expertise. To illustrate that this core is more than just a service core and serves as an important intellectual resource, we describe a project that is representative of the core's capability to address the evolving needs of the PPG membership.